1. Field of the Invention
The present invention relates to a fiber control apparatus in an open end spinning frame. More particularly, the present invention relates to an improved spinning rotor for use in an open end spinning frame.
2. Description of the Prior Art
As a conventional open end spinning frame, there is known an open end spinning frame of the self-exhaust type in which a plurality of exhaust vents are formed at the bottom of a rotor defining a spinning chamber in radial directions of the rotor. Air is exhausted from the spinning chamber through the exhaust vents by the centrifugal force produced by rotation of the rotor to produce a negative pressure within the spinning chamber. Fibers opened by combing roller disposed within a spinning body are carried from a fiber passage into the spinning chamber by this negative pressure. The fibers are caused to move and are deposited onto the inner circumferential surface of the rotor. Those deposited fibers are displaced to the sliding wall of the rotor by the rotary centrifugal force of the rotor. The fibers are further gathered in the form of a ribbon in a gathering groove. The ribbon of fibers is withdrawn continuously from a yarn guide hole formed in the central portion of a separator to create spun yarns.
In this spinning frame, the factors displacing the fibers to the sliding wall of the rotor are the rotary centrifugal force of the rotor and the rotary stream of accompanying air generated by the viscosity between the sliding wall and air. It has been interpreted that, if we consider the speed variation of this rotary stream in relation to the radial position of the spinning chamber, the speed of the rotary stream with respect to the radial position of the spinning chamber increases toward the sliding wall from the rotary center of the rotor. Such speed variation of the rotary stream is hereinafter refered to as the speed distribution of the rotary stream. It has also been considered that the above-mentioned speed distribution and the pressure thereof are important factors dominating the behavior of fibers in the spinning chamber and, hence, influencing the quality of the resultant yarn.